Hyperfiltration scoop apparatus and method

Abstract

The efficiency of membrane separation is enhanced in a hyperfiltration process by scooping off controlled amounts of the boundary layer at desired points along the flow path where useful concentrations have been achieved avoiding the necessity of bringing the entire flow up to desired concentration. The use of porous stainless steel supports with membranes formed therein in situ after fabrication from the pipe sections in a single pass configuration is especially advantageous with scoop apparatus spaced along the length of the stainless supports.

What is claimed: 
     
       1. For use in a hyperfiltration apparatus for increasing the concentration of an effluent from a fluid treatment process, the improvement comprising: a permeable tubular structural support member;   a membrane supported by said tubular structural support member extending along said member internally thereof presenting an open elongated flow path;   an opening in said membrane intermediate the ends of said member;   an opening in said support member in register with said opening in said membrane for flow of boundary layer fluid therethrough; and   means for collecting boundary layer fluid passing through said openings;   whereby the fluid flow very near a membrane fluid interface is highly concentrated and may be removed as a concentrate through said openings for collection.   
     
     
       2. The structure set forth in claim 1 including spaced structural support sections and spaced membrane portions forming circumferential openings. 
     
     
       3. The structure set forth in claim 1 including spaced membrane portions with a continuous support member. 
     
     
       4. The structure set forth in claim 1 including an inwardly projecting circumferential member extending across said boundary layer fluid and then facing upstream. 
     
     
       5. The structure set forth in claims, 1, 2, 3, or 4 wherein said structural support member is fabricated from sections of porous stainless metallicpipe and wherein said membrane is deposited in situ upon the interior of said support member after fabrication. 
     
     
       6. The method of increasing the concentration of an effluent from a fluid treatment process comprising the steps of: passing said effluent under pressure into an elongated tubular continuous hyperfiltration apparatus having a membrane extending along said apparatus internally thereof presenting an open elongated flow path;   forming a boundary layer of predetermined concentration after passage of said effluent through at least a substantial portion of said apparatus;   scooping away the boundary layer of said perdetermined concentration retaining less concentrated portions of effluent; and   utilizing the boundary layer thus scooped away in said fluid treatment process.   
     
     
       7. The method set forth in claim 6 including recycling said remaining less concentrated portions of effluent and passing same with the first mentioned effluent into said hyperfiltration aparatus.